Annealing temperature-dependent crystallinity and photocurrent response of anodic nanoporous iron oxide film. Issue 12 (9th June 2016)

• Record Type: Journal Article
• Authors: Rozana, Monna; Abdul Razak, Khairunisak; Yew, Cheong Kuan; Lockman, Zainovia; Kawamura, Go; Matsuda, Atsunori
• Is Part Of: Journal of materials research. Volume 31:Issue 12(2016)
• Page Start: 1681
• Page End: 1690
• Publication Date: 2016-06-09
• Subjects: annealing, -- film, -- nanostructure; Materials -- Research -- Periodicals; 620.1105
• DOI: 10.1557/jmr.2016.206
• Languages: English
• ISSNs: 0884-2914

Abstract

Abstract: Abstract : The effects of annealing temperatures on the structure and photocurrent response of nanoporous iron oxide film prepared by anodization of iron foil in an ethylene glycol, NH4 F, and H2 O electrolyte were studied. The as-anodized anodic film was found to be rather amorphous and crystallized to predominantly α-Fe2 O3 upon annealing in nitrogen. Nitrogen was used as to reduce the thickening of the barrier layer which affects the photocurrent response of the oxide. However, annealing must be done above 300 °C to produce crystalline oxide but must be kept lower than 500 °C since high temperature promotes grain growth, destroying the nanoporous structure and also thickens the barrier layer, which significantly reduce the photocurrent of the film. Sample annealed at 450 °C in nitrogen has the highest photocurrent of 1.04 mA/cm 2 (0.5 V versus Ag/AgCl in 1 M NaOH) compared to 0.13 mA/cm 2 at 0.5 V for air-annealed sample.